/*
 * Copyright 2002-2017 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.jdbc.core.metadata;

import java.util.Arrays;
import java.util.List;

import javax.sql.DataSource;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.springframework.dao.DataAccessResourceFailureException;
import org.springframework.jdbc.support.JdbcUtils;
import org.springframework.jdbc.support.MetaDataAccessException;

/**
 * Factory used to create a {@link CallMetaDataProvider} implementation
 * based on the type of database being used.
 *
 * @author Thomas Risberg
 * @author Juergen Hoeller
 * @since 2.5
 */
public class CallMetaDataProviderFactory {

    /**
     * List of supported database products for procedure calls
     */
    public static final List<String> supportedDatabaseProductsForProcedures = Arrays.asList(
            "Apache Derby",
            "DB2",
            "MySQL",
            "Microsoft SQL Server",
            "Oracle",
            "PostgreSQL",
            "Sybase"
    );

    /**
     * List of supported database products for function calls
     */
    public static final List<String> supportedDatabaseProductsForFunctions = Arrays.asList(
            "MySQL",
            "Microsoft SQL Server",
            "Oracle",
            "PostgreSQL"
    );

    private static final Log logger = LogFactory.getLog(CallMetaDataProviderFactory.class);


    /**
     * Create a CallMetaDataProvider based on the database metadata
     *
     * @param dataSource used to retrieve metadata
     * @param context the class that holds configuration and metadata
     * @return instance of the CallMetaDataProvider implementation to be used
     */
    static public CallMetaDataProvider createMetaDataProvider(DataSource dataSource,
            final CallMetaDataContext context) {
        try {
            CallMetaDataProvider result =
                    (CallMetaDataProvider) JdbcUtils.extractDatabaseMetaData(dataSource, databaseMetaData -> {
                        String databaseProductName =
                                JdbcUtils.commonDatabaseName(databaseMetaData.getDatabaseProductName());
                        boolean accessProcedureColumnMetaData = context.isAccessCallParameterMetaData();
                        if (context.isFunction()) {
                            if (!supportedDatabaseProductsForFunctions.contains(databaseProductName)) {
                                if (logger.isWarnEnabled()) {
                                    logger.warn(databaseProductName
                                            + " is not one of the databases fully supported for function calls " +
                                            "-- supported are: " + supportedDatabaseProductsForFunctions);
                                }
                                if (accessProcedureColumnMetaData) {
                                    logger.warn(
                                            "Metadata processing disabled - you must specify all parameters "
                                                    + "explicitly");
                                    accessProcedureColumnMetaData = false;
                                }
                            }
                        } else {
                            if (!supportedDatabaseProductsForProcedures.contains(databaseProductName)) {
                                if (logger.isWarnEnabled()) {
                                    logger.warn(databaseProductName
                                            + " is not one of the databases fully supported for procedure calls " +
                                            "-- supported are: " + supportedDatabaseProductsForProcedures);
                                }
                                if (accessProcedureColumnMetaData) {
                                    logger.warn(
                                            "Metadata processing disabled - you must specify all parameters "
                                                    + "explicitly");
                                    accessProcedureColumnMetaData = false;
                                }
                            }
                        }
                        CallMetaDataProvider provider;
                        if ("Oracle".equals(databaseProductName)) {
                            provider = new OracleCallMetaDataProvider(databaseMetaData);
                        } else if ("DB2".equals(databaseProductName)) {
                            provider = new Db2CallMetaDataProvider((databaseMetaData));
                        } else if ("Apache Derby".equals(databaseProductName)) {
                            provider = new DerbyCallMetaDataProvider((databaseMetaData));
                        } else if ("PostgreSQL".equals(databaseProductName)) {
                            provider = new PostgresCallMetaDataProvider((databaseMetaData));
                        } else if ("Sybase".equals(databaseProductName)) {
                            provider = new SybaseCallMetaDataProvider((databaseMetaData));
                        } else if ("Microsoft SQL Server".equals(databaseProductName)) {
                            provider = new SqlServerCallMetaDataProvider((databaseMetaData));
                        } else if ("HDB".equals(databaseProductName)) {
                            provider = new HanaCallMetaDataProvider((databaseMetaData));
                        } else {
                            provider = new GenericCallMetaDataProvider(databaseMetaData);
                        }
                        if (logger.isDebugEnabled()) {
                            logger.debug("Using " + provider.getClass().getName());
                        }
                        provider.initializeWithMetaData(databaseMetaData);
                        if (accessProcedureColumnMetaData) {
                            provider.initializeWithProcedureColumnMetaData(databaseMetaData,
                                    context.getCatalogName(), context.getSchemaName(), context.getProcedureName());
                        }
                        return provider;
                    });
            return result;
        } catch (MetaDataAccessException ex) {
            throw new DataAccessResourceFailureException("Error retrieving database metadata", ex);
        }
    }

}
